How do you simulate the EXPLAIN of an embedded SQL statement in SPUFI/QMF? Give an example with a host variable in WHERE clause.)

Use a question mark in place of a host variable ( or an unknown value ). e.g.

SELECT EMP_NAME

FROM EMP

WHERE EMP_SALARY > ?

 What are the isolation levels possible ?

CS: Cursor Stability

RR: Repeatable Read

 What is the difference between CS and RR isolation levels?

CS: Releases the lock on a page after use

RR: Retains all locks acquired till end of transaction

 Where do you specify them ?

ISOLATION LEVEL is a parameter for the bind process.

 When do you specify the isolation level? How?

During the BIND process. ISOLATION ( CS/RR )…

I use CS and update a page. Will the lock be released after I am done with that page?

No.

What are the various locking levels available?

PAGE, TABLE, TABLESPACE

 How does DB2 determine what lock-size to use?

1. Based on the lock-size given while creating the tablespace

2. Programmer can direct the DB2 what lock-size to use

3. If lock-size ANY is specified, DB2 usually chooses a lock-size of PAGE


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